JPH03153423A - Full time four-wheel driving device - Google Patents

Abstract

PURPOSE:To improve the performance of a full time four-wheel drive vehicle with a simple and inexpensive structure by adding a single limited differential mechanism in a double differential device differentially rotated between the left front axle and the right rear axle and between the right front axle and the left rear axle. CONSTITUTION:The right differential device 3 is provided in parallel with a driven gear 2 driven by a transfer gear 1, and the right planetary gear 5 is interlockingly connected to the left planetary gear 10 of the left differential device 8 via a drive shaft 7. The left side gear 11 of the left differential device 8 is connected to the left drive gear 14 and the left driven gear 15 via a viscous coupling 12, and the right side gear 16 is connected to the left front axle (not shown in the figure) via the left drive shaft 17 and the left pinion. The left side gear 23 of the right differential device 3 is connected to the right drive gear 25 and the right driven gear 26 via a circular shaft 24, and the right side gear 27 is connected to the right front axle (not shown in the figure) via the right drive shaft 28, the right pinion and the like.

Description

[Detailed description of the invention] (a) Industrial application field This invention relates to improvement of a constant four-wheel drive device.
Conventional technology In a permanent four-wheel drive system that uses three differentials including a center differential, the center differential requires a limiting differential or a differential lock mechanism, and it is difficult to fully limit the differential for all four wheels. (c) Problems to be Solved by the Invention This invention has the problem that it requires two additional limiting differential devices, making it complicated and expensive. It uses a double differential device that rotates differentially with the rear axle, and by simply adding only one differential lock mechanism or limiting differential mechanism, all four wheels are always limited differentially. The purpose is to obtain a driving device.

(d) Means for Solving the Problems Below, this invention will be explained with reference to the drawings.
1 is a plan sectional view showing the structure of a transaxle in a first embodiment applied to a manual transmission of the present invention, and FIG. 2 is a skeleton diagram of the power train. In this system, the double differential is divided into two parts, and the transfer gear 1
The drive shaft 7 is connected to the left planetary gear on the left planetary carrier 9 of the left differential 8 via the pin 6 of the right planetary gear 5 on the right planetary carrier 4 of the right differential 3, which is attached to the driven gear 2 driven by the The left side gear 11 is connected to the left drive gear 14 via a shell 13 on the outer periphery of the viscous coupling 12.
, rotates the left driven gear 15. Its right side gear 16
The left pinion 20 is interlocked with the left drive shaft 17 via a ball joint 18, 19, and the left front axle 22 is driven via a ring gear 21. The left side gear 23 of the right differential 3 rotates the right drive gear 25 and the right driven gear 26 via the circular shaft 24.The right side gear 27 rotates the right drive shaft 28 and the ball joint 18.19.
The right pinion 31 is interlocked with the right pinion 31, and the right front axle 33 is driven through the ring gear 32. Conventionally, this diagonal differential double differential has the characteristic of not allowing only one of the four wheels to spin, but the present invention has developed a limited differential that prevents even two of the four wheels from spinning. Both rings are completely possible.

(e) Operation: Initially, the output of the engine 34 is shifted through the main shaft 38 and counter shaft 39 of the engine shaft 35, clutch 36, and manual transmission 37, including the known lowest speed, and is then transferred through the transfer gear 1 to the left and right differential device 8. .3 through i, universal joint 40. Left and right propeller shafts intersecting 41.4
2, the right driven gear 26 connects to the left rear axle 45 via the spiral bevel left pinion 43 with low gear loss shown in FIG. The point that the right rear axle 48 is driven through the
Although it is similar to the permanent four-wheel drive system shown in the first embodiment of No. 95726, in the present invention, in order to obtain a large minimum ground clearance,
Each ring gear 21.32 and left and right final gears 44.47 are inside the wheels 49.50, 51.52 of the front and rear left and right axles.
Since the drive shaft 7 rotates in the opposite direction, the manual transmission 37 and the like are placed on the right side of the engine 34. The viscous cut spring 12 has the advantage of being much smaller and lighter. In a permanent four-wheel drive system that uses a conventional center differential, there are three types: between the left and right front wheels, between the left and right rear wheels, and between the center differential.
It would have been impossible to achieve limited differential differential for all four wheels without using two viscous couplings 12, but in this invention, the left and right differentials 8.63 are driven by the same driven gear 2. Therefore, the limited differential operation of only one viscous coupling 12 has the effect of completely limiting differential movement of all four wheels, which is useful for cost and weight reduction. Moreover, since each differential device uses a conventional type, the entire transaxle including the transfer gear 1 can be modified only slightly. As shown in Figure 3, the left and right front axles 22, 23 are provided with known multi-link suspension arms 77 to reduce the unsprung weight, and the left and right rear axles 45, 48 are also provided with known trailing arms 89, link arms 90, etc. It is installed to reduce the weight under the spring.

The steering shaft 91 is provided above and below the ball joint 19.

(F) Example According to the invention described in the specification of Published Patent Publication No. 63-219426, four worm gears are arranged in parallel to convert a Torsen type limiting differential into a double differential. In the present invention, only one simple Torsen differential device 53 using two worm gears is used, and as in the first embodiment, a complete limited differential of all four wheels can be achieved. You can get things done automatically. That is, the second embodiment shown in FIG. 5 is an application example using the ATS 4 including a very low speed stage, and the left differential
The left worm gear 56 that meshes with the coexisting worm 55 is connected to the left drive gear l.
11, and the right worm gear 58 meshing with the right worm 57 is configured to interlock the left drive shaft 17 via a spline 59. In this case, the Tosen differential gear 5
The limited differential effect of No. 3 also applies to the right differential device 3, and even if either of the coexisting right side gears 25 or 23 over-rotates due to idling, etc., they will rotate by the same drive shaft 7, so the torsen difference will be reduced. Over-rotation is not allowed unless the shell 92 of the drive device 53 over-rotates, so all four wheels 49.50.
51 and 52 all suppress extreme over-rotation and obtain a differential. As a result, the expensive TOSEN differential gear 53 is used at a relatively high speed position, so it is made smaller and lighter, and the effect of using only one gear can be maximized. In the third embodiment shown in FIG. 6, a double differential device similar to the third embodiment shown in FIG. The outer planetary gear 62 is connected to the right drive shaft 2 via the outer cloth side gear 63 by the two pins 61.
8. The right drive gear 25 is rotated through the external side gear 65 and the outer annular shaft 66, and the inner planetary gear 67 is rotated through the internal side gear 68, and the left drive shaft 17 and the inner left side gear 69 are rotated through the inner annular shaft 70 and the cylindrical shape. Clutch/L71
The left drive gear 14 is transmitted through. This is a so-called torque split system, and the multi-disc clutch 72 provided inside the clutch shelf 1 pressurizes the pump 73 through an oil passage 75 via a known hydraulic control mechanism 74, and pressurizes the left drive shaft 17. The pressure is applied from the center of the drive shaft 17 to the inner annular shaft 70 through an annular piston 76. This pressure contact force is controlled depending on the driving condition and the road surface to create an optimal limiting differential between the left drive shaft 17 and the inner annular shaft 70. give.

When the pressure is at its maximum, all four wheels make a single rotation, and the limiting differential reaches its peak, but normally it operates in the base intermediate pressure range, and the four wheels rotate to a moderate degree. 5
The two things that can be done are 1. The operation is similar to that of the second embodiment.

In each of these embodiments, two differential devices 3.8 are used as in the first embodiment, one double differential device is used as in the third embodiment, and It goes without saying that various types of clutches including torque split type clutches (for example, simple synchro clutches) or viscous couplings 12 can be used in combination depending on the application. Also, 1st to 6th
Although the illustrated embodiment is an application example in which the engine is placed horizontally, it is clear that this can be easily replaced and implemented also when the engine is placed vertically and a known double differential is used.

(g) Effects of the Invention As explained above, the present invention not only significantly improves the performance of a constant four-wheel drive vehicle by simply using one various limiting differential mechanism, but also reduces gear loss comparatively. It also has a large minimum ground clearance, and is effective in improving the performance of off-road vehicles by making it inexpensive, small, and lightweight.

[Brief explanation of the drawing]

FIG. 1 is a plan sectional view showing the structure of a transaxle according to a first embodiment of the present invention, FIG. 2 is a skeleton diagram of the transaxle, and FIG. 3 is a front sectional view of the front axle. , 4th
Figure 5 shows a cross-sectional plan view of the coexisting rear axle, Figure 5 shows a cross-sectional plan view showing the structure of the transaxle of the second embodiment, and Figure 6 shows a cross-sectional plan view showing the structure of the transaxle of the third embodiment, respectively. show. Explanation of symbols 78 Clutch 79 Case 80 Countershaft 81 Torque converter 2 83 4 5 6 7 8 Hand brake multi-disc clutch C2 Multi-disc clutch C1 Multi-disc clutch C3 Multi-disc brake one-way brake underdrive transmission

Claims (1)

[Claims] (1) The left drive gear and the left drive of the left differential in a double differential that rotates differentially between the left front axle and the right rear axle, or between the right front axle and the left rear axle. A constant four-wheel drive device characterized by a limited differential that is achieved by providing a viscous coupling between the shaft and the shaft by rotation of the same driven gear. (2) Using the double differential device set forth in claim 1, a multi-disc clutch is provided between the left and right drive gears, and the rotation difference between the left drive gear and the left drive shaft is controlled via a hydraulic control mechanism. 2. The constant four-wheel drive system according to claim 1, wherein the pressure contact of the multi-disc clutch is adjusted by a piston that is adjusted and press-contacted to provide a limited differential. (3) Of the double differential device described in claim 1, the left differential device is replaced with a limiting differential device that uses a worm and a worm gear, and the entire double differential device including the right differential device is simultaneously operated. The constant four-wheel drive device according to claim 1, characterized in that the limiting differential is carried out by the same limiting differential device. (4) The output of the engine is transmitted from the subshaft of the transmission located on the right side of the transmission through the transfer gear and driven gear, interlocking the double differential to the left and right propeller shafts, two ball joints, and the left and right front wheels. The left and right rear axles are connected via the pinion and ring gear installed inside the left and right front axles, and the left and right propeller shafts arranged in a K-shape, and through the left and right pinions and left and right final gears installed inside the left and right rear wheels. A constant four-wheel drive system according to claim 1, characterized in that a power train is used to drive the vehicle.